(一)观测目的 为了解聊城地区飞蝗发生时期,和主要植物的生长、发育时期的关系,以充实飞蝗的预测预报工作。 (二)观测的材料和方法 1957年4月于聊城五区设点进行观测,材料以蝗区有代表性的植物,小麦、枣树、棉花、谷子、高粱,各选四点,每种植物10棵,每隔3天观测记载一次,对杂草植物,因系农田,不宜进行观测。 (A) Objectives of the observation In order to understand the relationship between the occurrence of migratory locusts and the growth and development of major plants in Liaocheng, the forecasting work of migratory locusts should be enriched. (2) Materials and Methods of Observation Observed in April 1957 in the Liaocheng five districts, the materials were represented by representative plants in the locust area, wheat, jujube, cotton, millet, sorghum, 10, observed and recorded every 3 days once, weeds plants, because of the Department of farmland, should not be observed.